Apple watchOS up to 5.3.8/6.2.8/7.0.3 WebKit use after free

Summaryinfo

A vulnerability described as critical has been identified in Apple watchOS up to 5.3.8/6.2.8/7.0.3. Affected by this vulnerability is an unknown functionality of the component WebKit. Executing a manipulation can lead to use after free. This vulnerability appears as CVE-2020-27918. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Apple watchOS up to 5.3.8/6.2.8/7.0.3 (Smartwatch Operating System). It has been declared as critical. This vulnerability affects an unknown code block of the component WebKit. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was presented 11/05/2020 as HT211928 as confirmed advisory (Website). The advisory is shared for download at support.apple.com. This vulnerability was named CVE-2020-27918. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The advisory points out:

Processing maliciously crafted web content may lead to arbitrary code execution

The vulnerability scanner Nessus provides a plugin with the ID 241427 (RHEL 7 : webkitgtk4 (RHSA-2025:10364)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.3.9, 6.2.9 or 7.1 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

A use after free issue was addressed with improved memory management.

The vulnerability is also documented in the vulnerability database at Tenable (241427). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Smartwatch Operating System

Vendor

• Apple

Name

• watchOS

Version

• 5.3.0
• 5.3.1
• 5.3.2
• 5.3.3
• 5.3.4
• 5.3.5
• 5.3.6
• 5.3.7
• 5.3.8
• 6.2.0
• 6.2.1
• 6.2.2
• 6.2.3
• 6.2.4
• 6.2.5
• 6.2.6
• 6.2.7
• 6.2.8
• 7.0.0
• 7.0.1
• 7.0.2
• 7.0.3

License

• commercial

Website

• Vendor: https://www.apple.com/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

Discussion